1. Field of the Invention
The present general inventive concept relates to a heat exchanger that is applicable to a ventilator, and more particularly, to a heat exchanger that is able to minimize leakage of air from corners therein.
2. Description of the Related Art
Generally, a ventilator expels indoor air outdoors and sucks in outdoor air indoors to ventilate an indoor space. In ventilating the indoor space, warm or cold indoor air must be discharged outdoors and warm or cold outdoor air must be introduced indoors. Therefore, ventilating without any filtering process causes much heat loss in the indoor space and may cause an enormous amount of wasted electric power for air-conditioning of the indoor space. To solve this problem, the ventilator is provided with a heat exchanger to exchange heat between air discharged outdoors and air sucked indoors to recycle wasted heat or cold.
An example of such a heat exchanger is disclosed in Japanese Patent Laid-open Publication No. Hei 06-313694. The disclosed conventional heat exchanger includes a body, two metal plates, and four corner members. The body is formed by stacking heat-exchanging sheets and spacers alternately. The two metal plates are each disposed at opposite ends of the body respectively. The four corner members are each attached at one of four corners of the body and the plates respectively. Each of the four corner members has an L-shaped cross-section to fit to the corner of the heat exchanger body and is bonded to the heat exchanger body with silicon to prevent air from leaking through a gap between the corner member and the heat-exchanging sheets.
However, such a conventional heat exchanger has a structure that an inside corner of the corner member abuts the corner of the heat exchanger body. For this reason, a gap may be formed between the corner member and the heat exchanger body in a case that the sizes of the stacked heat-exchanging sheets and the spacers are incorrect. The gap causes air leakage.
Such an air leakage through the gap could be prevented to some extent by using adhesives such as silicon. However, in the conventional heat exchanger the corner member becomes loose from the heat exchanger body because silicon is applied between the corner member and the heat exchanger body. Further, if silicon is not applied uniformly, there still may be air leakage through the gap between the corner member and the heat exchanger body.
Such loosening of the corner member from the heat exchanger body causes a difficulty in mounting the heat exchanger to the ventilator. When the heat exchanger is mounted to the ventilator, the corner member is inserted into an inside of a guide rail provided at the ventilator. If the corner member becomes loose from the heat exchanger body, the corner member and the guide rail interfere with each other and cause a difficulty in mounting the heat exchanger to the ventilator.
Further, in the disclosed conventional heat exchanger, the metal plates disposed at the opposite ends of the heat exchanger and the corner member are secured to the heat exchanger by screw, so that the heat-exchanging sheets and the spacers may be damaged by the inserted screw and possibly cause air leakage.